Pivoted latch knitting needle



2 Nov. 30, 1965 w. E. SHEELER PIVQTED LATCH KNITTING NEEDLE Filed April30, 1962 3,220,221 PIVOTED LATCH KNITTING NEEDLE William E. Sheeler,Sinking Spring, Pa., assignor, by

rnesne assignments, to Textile Machine Works, Wyomissing, Pa., acorporation of Pennsylvania Filed Apr. 30, 1962, Ser. No. 191,197 1Claim. (Cl. 66-121) This invention relates to pivoted latch needles forknitting machines and more particularly to an improvement in thestructure of the head or hook of such needles.

In latch needles and particularly such needles for use in circularmachines for knitting sheer tubular fabric such as for ladies stockingsor the like, the upper or head end of the needle is provided with anoverhanging hook having a circular cross section which must be as littleas nineto ten-thousandths of an inch in diameter for the known finegauge machines. In forming the fabric stitches the needle is raisedduring which a previously formed stitch opens the latch of the needleand is cleared below the lower end thereof and yarn for a new stitch islaid over the needle between the hook and the open latch. The needle isthen lowered to form the new stitch during which the previously formedstitch closes the latch over the tip of the hook thereby permitting thelatter stitch to be knocked over or oif the head of the needle. Theseraising and lowering movements of the needle in forming the fabricstitches which usually occur at high speeds, usually two hundred or moretimes a minute, cause vibration in the overhanging hook which whencoupled with the light, rapidly repeated hammer-like blows on the tip ofthe hook as the latch is closed, rapidly fatigues the delicate structureof the hook and results in breakage thereof.

It is an object of the invention to provide a pivoted latch needle witha hook which is constructed to overcome the above mentioned and otherdefects and which will greatly increase the life of the needle in use.

Another object is to provide a pivoted latch needle with a hook having asubstantially rectangular cross section, the width of the rectangularsection corresponding to the normal permissible width of the hook of theneedle and the height of the rectangular section being greater than thenormal width of the hook.

A further object of the invention is to provide a method of forming aneedle having a butt at one end thereof, and a hook at the other endthereof which is adapted to be closed by a pivoted latch, said methodincluding the steps of forming the needle blank from material having athickness greater than that normal for .the needle, reducing thematerial of the upper end portion of the blank from which the hook is tobe formed in such a way that it becomes circular in cross section andhas a diameter which is greater than the normal diameter of the materialof the hook, bending the upper end portion to form the hook, andpressing the sides of the hook to change the cross-sectional shape ofthe material thereof from a circular to a rectangular shape having awidth corresponding to the normal diameter of the material of the hookand a height which is greater than the normal diameter of the materialof the hook.

With these and other objects in view, which will become apparent fromthe following detailed description of the illustrative embodiment of theinvention shown in the accompanying drawing, the invention comprises thenovel features of construction and method of producing the same, ashereinafter more particularly pointed out in the claims.

United States Patent ICC In the drawings:

FIGURE 1 is a side view on an enlarged scale of a pivot latch needleaccording to the instant invention;

FIG. 2 is a view on an enlarged scale of the upper or hook end of theneedle at one stage of its formation;

FIG. 3 is a cross-sectional view taken along the line and in thedirection of the arrows 3-3 of FIG. 2;

FIG. 4 is a view on an enlarged scale of the hook of the needle duringanother stage in its formation;

FIG. 5 is a view similar to FIG. 4 illustrating a further stage in theformation of the hook of the needle;

FIG. 6 is a view as seen from the right of FIG. 5; and

FIG. 7 is a cross-sectional view taken along the line and in thedirection of the arrows 77 of FIG. 5.

Referring to FIG. 1 of the drawing there is shown a needle 10 having ashank portion 11, a butt 12 at the lower end of the shank, a hook 15 atthe upper end of the shank, and a latch 16 mounted for pivotal movementadjacent to and adapted to cover the free end or tip of the hook.Commonly the needle, which is referred to hereinafter as gauge forpurposes of comparison, is punched or blanked out of flat metallic stockhaving a thickness of twelve-thousandths of an inch with the butt andshank being formed of varying widths to strengthen these portionsagainst both breaking and bending stresses during use. Following theforming of the blank the upper end is usually swaged or otherwisereduced to a circular cross-sectional shape of a diameter which isapproximately nine-thousandths of an inch, the portion of the shankadjacent the upper end is shaped to receive the pivoted latch and theupper end is then bent to form the hook 15.

Needles as described above are used in circular knitting machines forthe manufacture of fine gauge womens hosiery. Such machines normallyhave a cylinder diameter of 3% inches, the cylinders being slotted toreceive 400 or more needles. The machines also comprising a sinker-headsupporting a series of sinkers, one sinker being interposed between eachadjacent pair of needles.

During the operation of the needle to form yarn stitches, the needle israised to a high clearing level and yarn is laid over the needle betweenthe hook 15 and latch 16 which is at this time in open position asindicated in FIG. 1. As the needle is then lowered the yarn is caught inthe hook to be drawn or measured over the sinkers to form a stitch. Asthe needle is again raised to receive yarn for the next stitch the newlyformed stitch is held by the sinkers and stripped downwardly along theneedle to open the latch, if it has been closed, and as the needlecontinues to rise the new stitch is cleared below the end of the openlatch and onto the shank of the needle. After the yarn is again laidover the needle between the hook and open latch, the needle is againlowered to form the yarn into a new stitch and draw it through thepreviously formed stitch. During this downward movement of the needlethe previously formed stitch rides upwardly along the needle to closethe latch over the tip of the hook and as the needle continues itsdownward movement to its lowest position the previously formed stitchpasses upwardly over the closed latch and is knocked over the top ofneedle.

Because of the necessarily close spacing of the sinkers and the factthat the hook of each needle together with both legs of the stitch beingformed thereby must be moved through the space betwen adjacent sinkersthe maximum permissible width, i.e. the diameter in the conventionalneedle described above, of the material of the hook is limited. Normallyin order to provide as much strength in the hook as possible thediameter of the material of the hook for the different fine needlegauges approximates the permissible diameter for the needle count inwhich a needle of that gauge is to be employed. Hereinafter suchdiameter or width will be referred to as the normal width. In 80 gaugeneedles usually employed in such machines such normal width isnine-thousandths of an inch as previously mentioned.

The repeated raising and lowering movements of the needles in -formingthe stitches as described above, which may occur as many as two hundredor more times a minute, tend to set up a vibration in the hook and thisvibration together with the slight hammer blows on the tip of the hookas the latch is closed, causes the delicate structure of theconventional hook to become fatigued and results in breakage thereof.

In order to increase the strength of the hook of the needle and therebyincrease its resistance against fatigue without at the same timeincreasing its width beyond the normal width, the blank of the needle ofthe instant invention, the 80 gauge needle again being used for purposesof comparison, is preferably punched out of sheet material thicker thanthat normally used for a needle of such gauge, e.g. having a thicknessof thirteen-thousandths of an inch which is the normal thickness of thematerial from which a coarser or 75 gauge needle is formed. The upperportion of the needle blank from which the hook 15 is to be formed isreduced by swaging to a circular cross-sectional shape of a diameter,indicated at A in "FIG. 2, of approximately eleven-thousandths of aninch. Following bending of the upper end of the blank to form the hook15 as indicated in FIG. 4, the sides of the hook are flattened bypressing or the like to change the cross-sectional shape of the materialthereof to substantially a rectangle (FIGS. 6 and '7) having a widthindicated at B of approximately nine-thousandths of an inch whichcorresponds to the normal cross-sectional diameter of material of thehook of the usual 80 gauge needle as above set forth and the resultingdisplacement of material caused by the pressing action acts to increasethe vertical dimension or height of the rectangular area, indicated bythe dimension C in FIG. 7, from its original dimension ofeleven-thousandths of an inch to approximately tWelve-thousandths of aninch.

Thus there is provided a needle of a predetermined gauge in which thethickness of the shank portion is slightly greater than the normalthickness of the shank for the same gauge needle and in which thematerial of the hook portion is reshaped from a circular cross sectionto a substantially rectangular cross section having a width whichcorresponds to the normal permitted cross-sectional diameter of the hookfor a needle of this gauge and a height which is greater than the normalcross-sectional diameter of the hook.

It is to be understood that while the novel improvements have beendescribed herein in connection with an gauge latch needle, the inventionis not to be construed as limited to 80 gauge needles but as beingapplicable to any time gauge later needle in which the above mentionedproblems are present.

The improvements specifically shown and described by which the. abovedescribed results are obtained can be changed and modified in variousways without departing from the invention herein disclosed andhereinafter claimed.

What is claimed is:

A pivoted latch knitting needle of a predetermined gauge having a shank,a butt at one end of said shank and a hook at the other end of saidshank, and a pivoted latch for closing said hook, said shank and butthaving a width between the sides thereof which is greater than thenormal width of said needle of predetermined gauge, and said hook beingsubstantially rectangular in cross section, the Width of said rectanglecorresponding substantially to the normal width of said hook of saidneedle of predetermined gauge and the height of said rectangle beinggreater than said width.

References Cited by the Examiner UNITED STATES PATENTS 140,150 6/1973Mayne 163-5 140,611 7/1973 Bullard 163-5 485,021 10/1992 Sprowles 66-1232,685,787 8/1954 Noe 66121 2,854,836 10/1958 Morris 66-121 RUSSELL C.MADER, Primary Examiner.

DONALD W. PARKER, Examiner.

